# chemistty density question

Discussion in 'MCAT Study Question Q&A' started by INOHELP, Aug 11, 2011.

1. ### INOHELP 7+ Year Member

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If a solute is added with a certain density to a solution of a different density and it gets completely dissolved, is the new solution density a random number or a sum of the 2 densities or what??

2. ### inaccensa 7+ Year Member

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I think since density is an intensive property, you cant really sum up the densities,
although i would like a better explanation too

3. OP

### INOHELP 7+ Year Member

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Nvm I think I figured it out... It was confusig me to frustration but because the solvent completely dissolves, if the solute is more dense, It will increase the grams per volume. If lower density, it will lower the gram per volume.

I couldn't solve a problem in my br book for an hour..

4. ### inaccensa 7+ Year Member

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Are you saying that it is a sum of the individual densities?

5. ### MD Odyssey 2+ Year Member

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To find the new density, you would need to know the resulting mass of the solution and the new volume.

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6. ### inaccensa 7+ Year Member

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Is it sufficient to say that it wont be the sum of the densities of the 2

7. ### Sonyfan08 7+ Year Member

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I believe so. The new density should be somewhere between the two density values. Please correct me if I'm wrong.

8. ### MD Odyssey 2+ Year Member

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I'm inclined to agree with this, but I'm trying to come up with a counter-example. This sounds like a rather pathological discussion and I don't really see any immediate application. The density of a solid or liquid is defined as its mass per unit volume - adding densities directly doesn't make any sense to me.

Also, an observation I should make which probably IS relevant, is that some of these quantities change with things like temperature, particularly density. This is why molarity is not a constant - the volume of a liquid depends upon its density. Something to keep in mind.

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